If one were to make a list of the most influential TV series that almost nobody watched, HBO’s The Larry Sanders Show would be at the top. During its 1992-1998 run, it never got the industry accolades fans felt it deserved, and although it routinely ended up on critics’ year-end Top 10 lists, it got a meager handful of Emmy nominations and just three awards, a paltry number for a series that was often called the best thing on TV. And it rarely drew more than a couple million viewers per episode, a decent number for a premium channel in the pre-Sopranos era, but puny by broadcast network standards.

History, on the other hand, has rendered a glowing verdict. Created by actor-writer Garry Shandling and Dennis Klein, The Larry Sanders Show changed the look and feel of TV comedy. Its influence was felt almost immediately, and its impact continues to resonate. Although it wasn’t the first half-hour series to strip-mine the comedy of embarrassment, affect a laid-back, naturalistic style, or do without a score or a laugh track (except in the talk show sequences), the program’s combination of these elements was so distinctive that they amounted to a new template—one that subsequent programs borrowed and customized. From actor-writer-producer Ken Finkleman’s seriocomic Canadian series The Newsroom through the British and American versions of The Office and NBC’s current hit 30 Rock, which often feels like Larry Sanders played at double-speed, the series evokes that apocryphal line about Velvet Underground: Three thousand people bought their first album, and every one of them started a band.

Conan’s not the only one to use Shandling as a sounding board. For the past five years especially, the 60-year-old comic, who counts both George Carlin and Johnny Carson as mentors, has devoted himself to mentoring others. A generation of people at the top creative rungs of Hollywood credit Shandling with shaping both their material and their careers.

“There are so many people who lean on him to be their sage in these matters of what’s dramatic—not just what’s funny, but what’s effective, and what’s real, and why what’s funny is what’s real,” says Robert Downey Jr., who compares Shandling to “a Jewish E.T. He’s kind of vulnerable while at the same time very probing. And he’s got serious opinions.”

Iron Man 2 director Jon Favreau dubs him “the Godfather.” Baron Cohen sought Shandling’s advice on both Borat and Brüno. Silverman says Shandling has taught her how to embrace the silences during her stand-up act. And Apatow still counts the night Shandling hired him to write jokes for the 1991 Grammy Awards show as “the biggest break of my career.” Apatow later wrote for The Larry Sanders Show, and their collaboration continues: Shandling often attends table reads of Apatow’s films and gives notes on the scripts. (Apatow says Shandling had a “monumental” effect on The 40-Year-Old Virgin.) “There’s nobody better in the world than Garry at telling me what’s working and what’s not,” Apatow says. “I’m just very lucky that I’ve had his input.”